From mboxrd@z Thu Jan 1 00:00:00 1970 From: dick.streefland@xs4all.nl (Dick Streefland) Subject: Re: resync on every raidstart Date: Tue, 23 Sep 2003 20:43:04 -0000 Sender: linux-raid-owner@vger.kernel.org Message-ID: References: <7e6d.3f6de874.1ece7@altium.nl> <16239.60542.191148.816664@notabene.cse.unsw.edu.au> Reply-To: dick.streefland@xs4all.nl (Dick Streefland) Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: To: linux-raid@vger.kernel.org List-Id: linux-raid.ids Neil Brown wrote: | I cannot reproduce this. | Does it happen with real devices, or only loopback devices? | | Can you try with mdadm and see if that makes a difference? | | After raidstop, and before raidstart, can you | | mdadm -E /dev/loop1 | mdadm -E /dev/loop2 | | and show me the results? This is the output of mdadm-1.3.0: # mdadm -E /dev/loop1 /dev/loop1: Magic : a92b4efc Version : 00.90.00 UUID : 44f2804a:f7890a34:bd644666:becddad4 Creation Time : Tue Sep 23 21:08:17 2003 Raid Level : raid1 Device Size : 10176 (9.94 MiB 10.42 MB) Raid Devices : 2 Total Devices : 2 Preferred Minor : 0 Update Time : Tue Sep 23 21:08:33 2003 State : dirty, no-errors Active Devices : 2 Working Devices : 2 Failed Devices : 0 Spare Devices : 0 Checksum : e0ba675d - correct Events : 0.2 Number Major Minor RaidDevice State this 0 7 1 0 active sync /dev/loop1 0 0 7 1 0 active sync /dev/loop1 1 1 7 2 1 active sync /dev/loop2 # mdadm -E /dev/loop2 /dev/loop2: Magic : a92b4efc Version : 00.90.00 UUID : 44f2804a:f7890a34:bd644666:becddad4 Creation Time : Tue Sep 23 21:08:17 2003 Raid Level : raid1 Device Size : 10176 (9.94 MiB 10.42 MB) Raid Devices : 2 Total Devices : 2 Preferred Minor : 0 Update Time : Tue Sep 23 21:08:33 2003 State : dirty, no-errors Active Devices : 2 Working Devices : 2 Failed Devices : 0 Spare Devices : 0 Checksum : e0ba6760 - correct Events : 0.2 Number Major Minor RaidDevice State this 1 7 2 1 active sync /dev/loop2 0 0 7 1 0 active sync /dev/loop1 1 1 7 2 1 active sync /dev/loop2 I guess the "dirty" state is the problem? I also created a RAID1 array on another machine (2.6.0-test5 kernel, raidtools-1.00.3, mdadm-0.7.2) with real disks: # mkraid /dev/md3 handling MD device /dev/md3 analyzing super-block disk 0: /dev/hda3, 535752kB, raid superblock at 535680kB disk 1: /dev/hdb3, 535752kB, raid superblock at 535680kB ... waiting for sync completion ... # mdadm -E /dev/hda3 /dev/hda3: Magic : a92b4efc Version : 00.90.00 UUID : 8e85542d:e073310b:b5478b9a:67ea873f Creation Time : Tue Sep 23 21:38:39 2003 Raid Level : raid1 Device Size : 535680 (523.12 MiB 548.53 MB) Raid Disks : 2 Total Disks : 2 Preferred Minor : 3 Update Time : Tue Sep 23 21:49:36 2003 State : dirty, no-errors Active Drives : 2 Working Drives : 2 Failed Drives : 0 Spare Drives : 0 Checksum : b43f696d - correct Events : 0.1 Number Major Minor RaidDisk State this 0 3 3 0 active sync /dev/hda3 0 0 3 3 0 active sync /dev/hda3 1 1 3 67 1 active sync /dev/hdb3 # raidstop /dev/md3 # mdadm -E /dev/hda3 /dev/hda3: Magic : a92b4efc Version : 00.90.00 UUID : 8e85542d:e073310b:b5478b9a:67ea873f Creation Time : Tue Sep 23 21:38:39 2003 Raid Level : raid1 Device Size : 535680 (523.12 MiB 548.53 MB) Raid Disks : 2 Total Disks : 2 Preferred Minor : 3 Update Time : Tue Sep 23 21:50:45 2003 State : dirty, no-errors Active Drives : 2 Working Drives : 2 Failed Drives : 0 Spare Drives : 0 Checksum : b43f69b4 - correct Events : 0.2 Number Major Minor RaidDisk State this 0 3 3 0 active sync /dev/hda3 0 0 3 3 0 active sync /dev/hda3 1 1 3 67 1 active sync /dev/hdb3 A raidstart resulted in a second resync, but after that, it is clean: # mdadm -E /dev/hda3 /dev/hda3: Magic : a92b4efc Version : 00.90.00 UUID : 8e85542d:e073310b:b5478b9a:67ea873f Creation Time : Tue Sep 23 21:38:39 2003 Raid Level : raid1 Device Size : 535680 (523.12 MiB 548.53 MB) Raid Disks : 2 Total Disks : 2 Preferred Minor : 3 Update Time : Tue Sep 23 22:20:08 2003 State : clean, no-errors Active Drives : 2 Working Drives : 2 Failed Drives : 0 Spare Drives : 0 Checksum : b43f709c - correct Events : 0.4 Number Major Minor RaidDisk State this 0 3 3 0 active sync /dev/hda3 0 0 3 3 0 active sync /dev/hda3 1 1 3 67 1 active sync /dev/hdb3 However, the RAID1 array on the loopback devices stays "dirty", even after multiple raidstop/raidstart commands. -- Dick Streefland //// De Bilt dick.streefland@xs4all.nl (@ @) The Netherlands ------------------------------oOO--(_)--OOo------------------